The Vandebilt/Centers for Disease Control study came to this conclusion after examining data from kids' visits to doctors' offices, emergency rooms and outpatients clinics.
Dr. Carlos G. Grijalva and colleagues analyzed the effect of pneumococcal vaccine on otitis media, which are painful middle ear infections.
More than four out of five children get at least one ear infection before the age of 3. It is the most common reason antibiotics are prescribed to children.
Pneumococcal bacteria causes 30 to 55 percent of ear infections in children.
Grijalva and his team say, "Our results suggest a significant protective effect of the [pneumococcal] vaccination program in the U.S. outpatient setting, with a substantial decline in otitis media visit rates."
The authors say the study likely underestimates the effectiveness of the vaccine, which was introduced in 2000. This is because the study includes a time when the vaccine was in short supply, as well as a year when the vaccine did not match the strain of pneumococcal bug causing ear infections.
The study is published in the Sept. 5 issue of the journal "Pediatrics."
